1) Field of the Disclosure
The disclosure relates generally to stabilizer torque box assemblies and methods, and more particularly, to horizontal and vertical stabilizer torque box assemblies and methods for vehicles.
2) Description of Related Art
Thermoplastic composite structures or parts are used in a wide variety of applications, including in the manufacture of aircraft, spacecraft, rotorcraft, watercraft, automobiles, trucks, and other composite structures. In aircraft construction, thermoplastic composite structures or parts are used in increasing quantities to form the fuselage, wings, tail section, skin panels, and other components. In particular, parts of the aircraft horizontal stabilizers, also known as the horizontal tail, and parts of the aircraft vertical stabilizers, also known as a vertical tail, may be constructed of thermoplastic composite materials.
Known designs exist for aircraft thermoplastic composite and metal horizontal and vertical stabilizers that utilize either skin reinforced with stringers and stabilized by multiple ribs or multi-spar designs. For example, known horizontal or vertical stabilizers for large aircraft may be constructed of three spars and multiple ribs and stringers. The primary bending loads may be carried by stressed skins, and stringers inside thereof, in torque boxes, spaced forward and aft between a front spar and a rear spar. The ribs, extending forward and aft, stabilize the skin and stringers (e.g., shorten the stringer lengths) and provide load paths for concentrated transverse loads such as horizontal stabilizer pivot and elevator hinges. However, such known horizontal and vertical stabilizer designs may have an increased weight due to the multiple stringers and ribs used to stabilize the skin (e.g., prevent skin buckling due to compression loads).
In addition, known designs exist for aircraft composite and metal horizontal and vertical stabilizers that utilize honeycomb sandwich structures to eliminate the use of stringers and some of the ribs. However, where the stringers are eliminated, the structural arrangement may require the addition of intermediate spars which may eliminate any weight savings provided by the honeycomb sandwich structure used between the ribs and spars.
In addition, known methods and systems for fabricating and installing aircraft horizontal or vertical stabilizers include manual methods and systems and typically require multiple sets of tooling and molding operations. Such known methods and systems may apply pressure via each internal mandrel forcing all of the parts together. This may limit or prevent fabrication and processing techniques that use braiding machines to braid thermoplastic composite materials because once parts are assembled together, it may be difficult, if not impossible, to put the assembled parts through the braiding machine. Moreover, such known methods and systems for fabricating aircraft horizontal or vertical stabilizers may require increased time and increased labor which, in turn, may increase fabrication costs.
Accordingly, there is a need in the art for improved horizontal and vertical stabilizer torque box assemblies for vehicles and improved methods for fabricating such horizontal and vertical stabilizer torque box assemblies for vehicles that provide advantages over known assemblies, devices, systems and methods.